MAKE calls this a huge XY table. Crunchgear thinks it's kind of a mouse-controlled Etch-A-Sketch. All I know is, it uses a mouse, three skateboards and an Arduino microcontroller. But for what purpose?

I suppose it could be used as an inexact Etch-A-Sketch, using three skateboards for linear movement, but it seems like an awful lot of effort (and space—it must take up an entire garage!) for that. So help me out: What could this thing be used for? Should I be scared or excited? [MAKE via Crunchgear]